Emergency button



FIG. 1 is a front, right side, top perspective view of a emergency button showing my new design;

FIG. 2 is a front, left side, bottom perspective view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a left side elevational view thereof;

FIG. 6 is a right side elevational view thereof;

FIG. 7 is a top plan view thereof; and,

FIG. 8 is a bottom plan view thereof.

The broken lines depict portions of the emergency button that form no part of the claimed design. 

CLAIM The ornamental design for an emergency button, as shown and described. 